Morris Vedette cooling

[rwoodwar]

A (possibly) simple question on cooling a Vedette engine that powers a 7m launch I bought last year...

The cooling system works, water comes in directly from the river, through the weed filter, then up into the water pump that has a brass grease cap for pushing grease into the housing to allow the impeller to draw up water.

I would like to simplify this but without making significant changes to the aesthetic beauty of the engine.

At the moment I have to lift up the engine hatch, clamber over the windscreen and walk onto the nicely varnished foredeck in order to turn the grease cap to prime the water pump.
This has to be done every three to four times I start the engine, which since I have to go through locks, can be frequent.

So my question is...

could I sensibly put a self priming pump (I've seen Jabsco mentioned in several articles as being a good contender) on the rising pipe between the weed filter and the water pump. My idea is to push water through the current water pump to prime it. As I say I dont want to remove the original water pump for aesthetic reasons.

I guess an alternate approach might be to have some form of parallel setup so I could run a new pump off a switch on startup just to prime the system then let the old pump take over.

Any suggestions gratefully received. Happy to go and take some pictures if it would help.

Many thanks
Roger

[rwoodwar]

This is the setup, easier to see in a picture...[frame][/frame]

[smithskids]

Stuart Turner did a 12v centrefugal pump. Could be plumbed in to prime it. Or fit a hand plunger pump in to the system, I think zwicky made one. We had them in lifeboats when I was at sea.

[mike.perry]

Where abouts are you? I have a Morris 8 Vedette in my garage on casters so that I can move it around[frame][/frame]

[simmitc]

Isn't the grease required for lubrication, not just priming? If yes, then you'll still have to turn the cap anyway. Jabsco do a number of belt driven self priming pumps for marine use. What about using a remote greaser? These are often used on stern glands, but could easily be used in your case. Mount the grease reservoir and screw down plunger where you can get to it easily and then run a flexible tube to inject the grease where you need it.

[RobThomas]

Jabsco pump come in all sorts of designs. The GACO seals inside the one you have are not very watertight so you might find that the bearings within could be replaced with sealed ones that require no greasing. The Minor Owners Club had some waterpumps converted over to sealed bearings for the car engines.
The other option is the electric waterpump from a 7-series BMW that backs up the cooling system to provide flow after the engine stops (I think that was how they utilised it). £10 at a scrapyard.

[rwoodwar]

Fantastic advice, thank you.

The remote greaser is a great idea particularly as there is another greasing cap on the propeller stern gland, so I will definitely use it there. Just gone to the ASAP website and bought myself one.

I will also try Robs idea and see if I can replace the seals but it does also make sense to me that the grease might also be for lubrication. Is that likely to be the case or is water enough to lubricate or is it just not necessary?

Interestingly I have come to think that the previous owner didn't know about needing to use the grease cap to prime the water pump. I am pretty sure he ran it dry, if so without long term damage; he didn't mention it when I bought the boat (though he did say that the engine compartment might need more ventilation), and so I obviously did the same on my first trip... the temperature gauge went off the scale, following which a friendly engineer pointed out what was required!

Thanks again. Once I have sorted I will post the outcome.

[RobThomas]

There is very little pressure in that system so you don't need much to keep the water out of the bearings. Sealed-for-life would work quite well but you'd need lubricant in there and not water since H20 will kill the bearings. Not really practical to keep the bearings pressurised with grease other than the existing system you have, although, if you have a grease gun with a long hose on it you could have the handle located somewhere else so you can pump the handle from the cockpit. Doesn't need much quantity. Good idea to give the engine a pump of grease before yo park it up, too, so the bearings aren't left wet overnight.

The later 948cc Vedette Jabsco pump has GACO seals and a flexible rubber impeller in a bronze casting. Not sure if the early Vedette needs grease to get the pump to self-prime but the later engine doesn't seem to need it. Does it mention it in the handbook?

Good luck

Rob

[RobThomas]

Just been out to look at the bronze pump and there aren't any steel bearings in there so the Gaco seals just keep a modicum of white grease holding water out of the timing case and stopping the steel shaft from grinding against the bronze body.

That is a post 1952 engine, by the look of it.

[rwoodwar]

Thanks everyone. Remote greaser now installed and working fine! No more clamouring onto the foredeck in the middle of the river...